President Trump met with congressional leaders on Capitol Hill after meeting with business and union leaders at the White House. (Reuters)

Days after being sworn in, President Trump insisted to congressional leaders invited to a reception at the White House that he would have won the popular vote had it not been for millions of illegal votes, according to people familiar with the meeting.

Trump has repeatedly claimed, without evidence, that widespread voter fraud caused him to lose the popular vote to Hillary Clinton, even while he clinched the presidency with an electoral college victory.

Two people familiar with the meeting said Trump spent about 10 minutes at the start of the bipartisan gathering rehashing the campaign. He also told them that between 3 million and 5 million illegal votes caused him to lose the popular vote.

The discussion about Trump's election victory and his claim that he would have won the popular vote was confirmed by a third person familiar with the meeting.

House Majority Leader Kevin McCarthy (R-Calif.) alluded to Trump's comments as he returned to the Capitol from the meeting Monday night.

“We talked about different electoral college, popular votes, going through the different ones,” McCarthy said. “Well, we talked about going back through past elections. Everyone in there goes through elections and stuff, so everybody's giving their different histories of different parts.”

Asked by reporters after the meeting if Trump made any surprising statements at the gathering, House Minority Leader Nancy Pelosi (D-Calif.) replied, “Well, I won’t even go into that.”